X-ray specs that allow you to see under the clothes of a ravishing beauty remain a fiction from the back pages of gentlemen’s literature. But MIT researchers have found a way to “see” past a solid wall.
The team have come up with a new twist on radar, which works by bouncing radio waves off objects and deciphering their position. That’s a problem because standard radio waves can penetrate material such as concrete any more than light can.
Instead the researchers have worked with S-band waves, which are in the same frequency waves as Wi-Fi, and then used extremely powerful signal amplifiers. That deals with the problem that less than 1 percent of the waves get through the wall, and less than 1 percent of those make it back through after bouncing off the target, leaving the signal around 0.0025 percent of its original strength.
The researchers have also set up a special filter which “removes” the information from the waves that simply bounce back from the wall and would otherwise dominate the results. They also experimented to find a wavelength that gave enough detail to give usable results, but kept the transmitter to around 8.5 feet, which is short enough to be mounted on a vehicle for military results.
In tests, the system was able to “see” through both 8-inch concrete and cinder-block walls from 20 feet away (in theory 60 feet would be the maximum), producing real-time video at 10.8 frames per second. Only moving objects can be picked up as the system works by comparing each “shot” to the last, but the tests show that the system on was detailed enough to pick up even the tiny movements of humans attempting to stand still. However, as things stand, most objects show up merely as blobs and it takes training to distinguish what they represent.